Installing LPG injectors is one of the main stages of installing gas equipment on a car. The stable operation of the engine on the gas mixture depends on whether the injectors are installed correctly. If gas injectors are installed correctly, the process of switching the engine to gas should not be noticeable either visually or audibly.

Inserting fittings into the intake manifold (theory)

The installation of HBO injectors consists of several stages, the main of which is inserting the fittings into the manifold. The fitting must be installed in such a way that the gas entering the manifold continues its movement through the air circulating there. This is one of the main conditions for correct insertion, although many inexperienced installers neglect it.

Thus, the fitting should be cut at an angle of 45 to 90 degrees along the air flow. The gas must flow in the direction of the air flow or perpendicular to it. The cutting angle should not exceed 90 degrees. In this case, the air moving through the manifold will prevent the flow of gas from the fitting. The gas will be under pressure in the pipe between the nozzle and the fitting. This moment will certainly affect the operation of the nozzle, and consequently the entire LPG system.

The second important point of the insertion is the location of the fitting relative to the center of the manifold pipe. For better mixing of gas and air, the insertion should be made as close to the center of the manifold pipe as possible. Of course, the reservoir geometry is not always circular. Oval and square or rectangular cross-sectional shapes are often found. The shape of the collector does not matter - the rule that the insertion should be carried out as close as possible to the center of the air flow always applies.

One of the nuances of inserting LPG injectors is the bifurcating sleeve. In this case, the insertion must be carried out either before bifurcation, or a double insertion must be used after bifurcation. It is highly not recommended to make a single cut after bifurcation has begun.

Another thing worth paying attention to is the distance between the fitting and the gasoline injector. For all embedded fittings, the distance between them and the gasoline injectors must be the same.

Also, the length of the pipes with which the fittings will be connected to the gas injectors should be the same. Please also note that the length of such pipes should be as short as possible!

Insertion into the LPG manifold (practice)

In order for the installation of HBO injectors to be carried out efficiently, it is imperative to dismantle the intake manifold. Many “experienced” installers do not do this, making the insertion “by eye”, which, of course, is not correct. But this method of installing nozzles saves them a lot of time.

• After removal, you need to mark the drilling locations. Once again, please note that the insertion must be made in the direction of the air flow or perpendicular to it. All fittings must be located at the same distance from the gasoline injectors. The cut should be as close to the middle of the channel as possible.
• Before marking, be sure to determine the location of the ramp with nozzles. The ramp should be located as close as possible to the fittings, and the connecting hoses between them should be as short as possible.

• You can use masking tape to mark the drilling location. Fasten it well to the manifold and draw the future location of the fittings and the location of the proposed holes.
• Please note that the optimal distance from the edge of the intake manifold to the insert should be in the range from 1.5 to 6 cm.
• Take a punch and mark the locations of future holes.
• Take a drill slightly smaller than the diameter of the intended hole and start drilling. After all the necessary holes have been drilled, take a drill of a larger diameter that matches the fitting and drill out the landing spots to the required diameter.
• Try to ensure that as little chips as possible get into the collector, then all the chips will need to be cleaned out.
• After finishing drilling, it is necessary to cut the thread. We screw in the fittings and seal them with high-temperature sealant. You can use a “thread locker” to prevent the connection from accidentally unscrewing.

I am sure that the majority of car owners who think about their car and those who have installed it, as well as many auto mechanics, and, of course, the LPG installers themselves are wondering: is it necessary to dismantle the intake manifold to install the LPG.

For those who don't quite understand what I'm talking about, I'll explain. The purpose of the manifold is to distribute the air flow among the engine cylinders and give it the necessary movement. In the place where the manifold approaches the engine itself (to the internal combustion engine head and to the intake valves), gasoline injectors are installed on each path (4 cylinders - 4 injectors). The gas engineer’s task is to install gas injectors in such a way that gas enters the manifold, namely into each path as close as possible to the injector and at such an angle that the gas flow is directed towards the valve.

And now we come to the question of how to supply gas to the intake manifold. Naturally, everything is quite simple: holes are drilled in each intake manifold tract (4 cylinders - 4 holes). After this, the thread is cut and the fitting is screwed onto the clamp and the hose from the gas injector is connected directly to the fitting itself.

Now let's look at everything in detail and point by point:

1. The fittings must be at the same distance from the intake valve;
2. The fittings must be at the same angle;
3. The fittings should “look” at the valves and not create turbulent flows in the manifold.

If all these points can be fulfilled, there is one more small “BUT”: what to do with the chips when drilling the manifold if it is not dismantled? It turns out that chips, whether they come from plastic or aluminum alloys, end up inside the collector.

I have visited the forums several times and opinions are divided there. But the majority insists that there is no need to remove the manifold, all the chips fly out into the exhaust during the first start and everything is fine, or it is necessary to drill with special drills that make the chips small.

I can say one thing why there are so many opinions. The reason for this is the process of dismantling the collector itself. It is sometimes very difficult to remove it, and sometimes it can take up to one day.

Therefore, many believe that it is easier to do without dismantling. And, of course, after removing the manifold, it may be necessary to replace the manifold gaskets, and this is a waste.

Let us now think simply and logically.

So that you and I can see, first of all, how much chips enter the collector after drilling and after cutting threads, I decided to film it. This is an aluminum manifold with .

As you can see, a lot of chips poured from one hole. There are as many as eight such holes on an 8-cylinder machine, plus one more for vacuum.

I thought, well, during the first start-up, all these chips fall directly into the combustion chamber. Surely there is a possibility of these chips getting under the valve. Consequences of burnt valves and loss of vehicle power. Since the walls of the chamber are lubricated with oil, there is a possibility that these chips, along with gasoline and oil, will stick to the walls, after which, after some time of use, scratches will appear, which will entail increased oil consumption and loss of power due to compression. Well, some of the chips will fly out into the exhaust system. I think anyone who has looked at the design of the catalytic element will immediately say that chips will not physically pass through such “microscopic” holes, and most likely they will become clogged.

After such reflections, I came to the conclusion: whether this car has an aluminum manifold, or a plastic one, it is better to remove it, despite certain difficulties and time.

Of course, it’s up to you to decide, but if they tell you that they drove it in the morning and picked it up in the evening, you should know that no one will stand on ceremony with your car. Usually in such places they can install several cars per day.

I decided to raise the issue of inserting fittings into the intake manifold. As it turns out, many installers do not know how to properly make a tie-in, and as a result, many have problems during operation.

With these problems, they turn to more qualified specialists, who identify violations of the rules installation of fittings in intake manifolds. As it turned out, a lot depends on the correct insertion and location of the fittings, first of all, mixture formation. Incorrect formation of a combustible mixture most often manifests itself as follows: , audible.

Some LPG installers, when clients come to them with the question: “What’s going on and why is the car behaving this way?” - they answer differently. Sometimes they blame bad gas, sometimes they criticize low-quality gas equipment, there are also those who simply say that the engine is gasoline and is not designed to run on gas, so they “sausage” it slightly. In general, as you understand, you can justify anything if you want; you can “pin” a lot of things on a gullible client. However, after several days or months of torment (depending on how much patience), the deceived and perplexed car owner turns to professionals who, after a little diagnostics, conclude that the LPG was installed in violation of the rules for installing fittings in the intake manifolds.

How to install the fitting into the manifold correctly?

Inserting the fitting into the manifold must be carried out strictly perpendicular to the flow of air passing inside the collector. If this is not possible, the fitting must be inserted into the manifold at a certain angle. The angle should be such that the gas coming from the fitting is easily picked up by the air flow. It is unacceptable to insert fittings against the air flow; such a violation will lead to obstruction of gas flow inside the fitting.

Centering is also important. The fitting that cuts into the channel should be directed strictly to the center, or as close to it as possible. The fitting must not be placed on the side or somewhere towards the collector wall. The central location contributes to effective mixture formation, the gas is perfectly dispersed with air, resulting in a good combustible mixture with high efficiency. If the shape of the collector is not round, but, for example, square or rectangular, it is necessary to install the fitting so that it “looks” at the center and effectively mixes with the air flow.

In the case of a bifurcated collector, the insertion must be made before or after the bifurcation; in this case, two fittings are installed.

Signs of correct insertion

• Smooth transition to gas (without drop in speed, jolts or twitching).
• The operation of the motor should not change.
• While driving, you should not feel any disturbance in the operation of the engine and no significant difference between operation on different types of fuel.

Installation is divided into several stages:

1. Installation of a remote refueling device.
2. Installation of the cylinder.
3. Installation of multi-valve, gas level sensor.
4. Laying gas mains and electrical cables.
5. Installation and connection of the gearbox.
6. Inserting fittings into the intake manifold and installing injectors.
7. Selection and installation of gas hoses, coolant hoses and vacuum hoses.

Installation of VZU

VZU installed either in the bumper or in the gas filler flap. If in the bumper, then preferably on the side where the gasoline filler neck is located. In any case, it is necessary to ensure that the filling connection is sufficiently rigid. After all, the gas filling hose has quite a large mass and can bend or break the connection point. If we place the VZU in the gasoline hatch, then it is necessary to have an adapter. Please note that in different countries, petrol pumps have different fuel nozzles. Therefore, when traveling to other countries, you need to have different adapters with you.

Methane filling devices are sometimes installed in close proximity to the cylinder.

Installation of the cylinder

Cylinder type, its displacement and location are discussed with the car owner from the very beginning. This is determined by its needs and ease of use. When choosing a specific cylinder, you should pay attention to internal cleanliness. The cylinder must be free of rust and other contaminants. All this dirt will go throughout the gas chain and can clog the system.

Particular attention must be paid to fasteners. The cylindrical cylinder is secured with two metal strips with rubber gaskets. As a rule, in the luggage compartment close to the rear wall. The cylinder must be oriented so as to have convenient access to the multivalve, since some multivalves have a gas shut-off valve.

The choice of a toroidal cylinder is related to the size of the car's spare wheel. The fastening is much simpler and consists of one powerful screw, usually included with the cylinder. A toroidal balloon has several advantages over a cylindrical one. This is primarily about preserving the entire luggage space. You can either not carry a spare wheel at all (if the car is driven in the city) or place it in a convenient place. Often the toroidal cylinder kit also includes a cover for a spare wheel.

For jeeps and other vehicles with an external spare wheel, the cylinder is mounted on the outside of the body. In this case, it is necessary to strengthen the installation as much as possible. All necessary fasteners should be provided in case of a vehicle accident. It is also necessary to ensure sealing of the multivalve and its electrical part.

Installation of a multivalve and gas level sensor.

Multivalves There are two types. With and without electric valve. It is better to use with an electric valve. In some countries, such multivalves are required. When choosing a multivalve, the choice of cylinder and engine power are important. The diameter of the supply line depends on the power. These are 6, 8 and even 10mm. When installing a multivalve into a cylinder, you must make sure that the float moves freely in the space of the cylinder. This guarantees not only the correct readings of the gas level sensor in the cylinder, but also its correct filling when refueling.

Level sensors There are different types, differing both in resistance and principle of operation. These can be resistive, magnetic and optical. Three wired and two. Before installation, make sure that this sensor is compatible with the gas computer. As a rule, it is already included in its kit.

Laying gas mains and electrical cables

Material supply lines(gas tubes) can be copper, plastic or steel. Steel should only be used for methane plants. Plastic tubes are increasingly used when installing gas equipment. They are much cheaper, do not corrode, and do not require additional insulation. However, due to their flexibility, a larger number of fastening elements are required. It is also necessary to pay attention to their temperature range in the low range. The laying and fastening of tubes should be carried out with special care, keeping in mind that cutting in with self-tapping screws can damage the internal equipment of the car. When connecting the tube to the gearbox, it is necessary to provide several turns of the tube in the form of a spiral. This will facilitate connection to the reducer and contribute to some heating of the liquid phase of the gas.

Installation and connection of the gearbox

Gearbox selection is primarily related to the power of the vehicle. The most undesirable choice is a gearbox with a lower calculated power than the power of the vehicle. At maximum modes, the gas pressure will drop and this can lead to a lean mixture. Constantly operating the vehicle in such modes can lead to burnout of the valves. It is possible to install a gearbox with a large power reserve, but there may be slight instability of pressure in low modes. In addition, high-power gearboxes remove more heat from the coolant, which can lead to insufficiently efficient operation of the stove.

For heat supply It is best to use interior heating for the gearbox. Make the connection parallel to the stove hoses. It is very convenient to use special pliers for this. They clamp the hoses before and after the intended cut. A total of four of these clamps are needed. This method can prevent coolant leakage. Tees are placed at the cut sites. The reducer pipes are connected to them. The gearbox must be installed on a rigid support and preferably with tees installed below. This ensures there are no air bubbles. It is also necessary to provide for ease of access to the control element of the gearbox. Very often you have to adjust the differential pressure.

Constant airflow is undesirable temperature sensor gearbox This may result in incorrect temperature readings. If it is impossible to avoid blowing, it is necessary to thermally insulate the wires entering the sensor itself. It is through them that the temperature is distorted.

Vacuum control the gearbox is carried out by connecting the corresponding fitting with a hose to the intake manifold. It is advisable to take the connection point closer to the throttle valve. The diameter of the hose must match the reducer fitting. It is not advisable to use the existing engine vacuum system. In it, the change in pressure may not occur immediately. This will lead to dips in the differential pressure with a sharp increase in power and, accordingly, to its emissions when it decreases. The same requirements should be followed when supplying vacuum to the MAP sensor.

Inserting fittings into the intake manifold and installing injectors

Particular care must be taken when installing fittings gas supply. This operation boils down to drilling holes in the intake manifold. The main thing is that the drilling chips do not get inside the collector. It's better to remove the manifold and drill it. The drilling locations should be closer to the intake valves. Drilling angle, in relation to the air flow, must be the same for all cylinders. This will lead to equal gas supply to different cylinders.

In some cases, due to the impossibility of installing a close gas supply, additional extension tubes are installed inside the manifold. This operation requires great knowledge and skills. Performed only on a removed manifold.

It is quite acceptable to use gas spacers for gasoline injectors. Then you can avoid drilling the collector and everything connected with it. But this is not always possible.

At the drilling points, threads are cut and fittings with reinforcing sealant are screwed in. Hose length gas pressure on all injectors should be minimal (up to 10cm) and always equal. Sometimes, it is better to use individual gas injectors rather than prefabricated gas injectors. The injectors must be rigidly mounted on the engine and located in places where there are no passing air flows. This also applies to the gas temperature sensor (cross) installed in the immediate vicinity. It is advisable to orient the injectors themselves with the coils vertically upward. This will reduce friction and armature production in the nozzle, and also prevent oil deposits from entering the armature channel.

Exist three types of rubber gas hoses: for gas, for coolant, for vacuum. Each must be used for its intended purpose. When installing equipment, try to ensure that the hose lengths are minimal. It is necessary to pay attention to the clamps. It is mandatory to install them at all joints of the coolant hoses and gas lines from the gearbox to the gas injectors. It is advisable to install clamps on the hoses from the injectors to the screws into the manifold. You can do without them on vacuum hoses, with the exception of turbocharged engines.

Rules for installing MAP sensor and temperature sensors.

For reliable and trouble-free operation MAP sensor it must be placed higher than the connection point of the crosspiece of the gas temperature sensor. This will prevent oil deposits from getting into it. The cross itself should be located closer to the gas injectors. It is undesirable to blow it with large air flows.

Installation of ECU, control buttons.

General rule placement of gas computers in the engine compartment it is with the connector facing down. This is guaranteed to eliminate the problem of water getting inside the block. Since the blocks generate a certain amount of heat, they should not be placed in close proximity to heated engine elements.

The control button is placed in any convenient place, allowing you to freely control its state